Dear Chimera Team, I'm currently trying to install BioPython using Chimera's Python copy on Mac OS X. Thanks to the Chimera Programming FAQ, I've already managed to install BioPython succesfully on Ubuntu, but on Mac OS X I get the following error: Error while importing Combine from /Applications/Chimera.app/ Contents/Resources/share: Traceback (most recent call last): File "/Applications/Chimera.app/Contents/Resources/share/chimera/extension/base.py", line 349, in _importExtension __import__(module) File "/Applications/Chimera.app/Contents/Resources/share/Combine/ChimeraExtension.py", line 32, in <module> balloon="Combine molecular models into new model", moleculesOnly=True) File "/Applications/Chimera.app/Contents/Resources/share/ModelPanel/base.py", line 40, in addButton "Button named '%s' already exists" % name KeyError: "Button named 'copy/combine...' already exists" Error while importing Ramachandran from /Applications/Chimera.app/ Contents/Resources/share: Traceback (most recent call last): File "/Applications/Chimera.app/Contents/Resources/share/chimera/extension/base.py", line 349, in _importExtension __import__(module) File "/Applications/Chimera.app/Contents/Resources/share/ Ramachandran/ChimeraExtension.py", line 29, in <module> ModelPanel.addButton("Ramachandran plot...", emo.modelPanelCB) File "/Applications/Chimera.app/Contents/Resources/share/ModelPanel/base.py", line 40, in addButton "Button named '%s' already exists" % name KeyError: "Button named 'Ramachandran plot...' already exists" running install running build running build_py running build_ext Error while processing 'setup.py install': TypeError: argument of type 'NoneType' is not iterable File "/Applications/Chimera.app/Contents/Resources/frameworks/ Python.framework/Versions/2.7/lib/python2.7/_osx_support.py", line 185, in _find_appropriate_compiler if 'llvm-gcc' in data: See reply log for Python traceback. Is there anything I can do to solve this problem? Best, Mateusz